There are 20 of them in all, but you only see combos appropriate for the gear it's applied to.

Comment by intuit

The "of the Bedrock" (parry/mastery) version of this belt is currently (first raid tier) BiS for both shield-wearing classes. It's very similar to the one off Omnitron heroic (dodge/mastery and same socket bonus) BUT this one has less strength, which leads to more of the important stats.

edit: You get about 20 less strength on this belt but 20 more avoidance (parry) when compared to the belt off Omnitron.